I spent my early teen years (in the late 60s…!) in Honolulu, where the epitome of cool was the archetypal haole surfer dude, sporting only the straightest and blondest of hair. My own curly black locks flagged me at once as irredeemably other, and I found this so disconcerting that I once considered shopping for a chemical cure: if I couldn’t be an ultra-cool surfer dude, I might at least resemble the likes of John Lennon. Somehow I resisted the urge, and in college five years later I was literally living under an ashkenazi ‘fro reminiscent of Abbie Hoffman’s on steroids. Now the years have combed out almost all of my curl, and I’m left with a thinning, graying mini-mane that in Euclidean terms is closer than ever before to my 14-year-old ideal of having “good hair”. Alas, the consolation hardly registers.

Let’s face it, for all sorts of reasons best studied by social scientists, hair has a strange, primitive power over one’s self-image, and I have never seen a film that better explores this fact from the point of view of at least one American community than Chris Rock’s inspired documentary, Good Hair, now available on DVD. Here’s the trailer-

As a philosopher, Jerry Fodor (of Rutgers University) is famous for his contrarian stances, and his recent book with Massimo Piattelli-Palmarini, What Darwin Got Wrong, has been stirring up a lot of discussion both in academic circles and on the web. To understand their criticism of Darwin’s theory of natural selection, it’s helpful to first consider a case of human design. Take arches, for instance. Arches were “selected for” by architects because they solved an important engineering problem: how to efficiently support certain sorts of structure. Along with arches come spandrels, those areas that fill the space between the arches-

Architects probably weren’t concerned with spandrels at all when they first designed arches, but since you can’t have arches without spandrels, the two are “endogenously linked”, and so are “co-extensive” – wherever you have a series of arches, you have spandrels. It’s important to keep in mind that although they are co-extensive in this way, ‘arch’ does not mean ‘spandrel’ (or include ‘spandrel’ in its meaning), and one can certainly think of an arch without thinking of a spandrel. Similarly, to adapt an old example, although ‘healthy creature with a heart’ is co-extensive with ‘healthy creature with a kidney’, the two expressions obviously do not have the same meaning. One way of putting this is to say that they have the same extensions (since they refer to the same creatures in the actual world), but different intensions. Finally, certain linguistic contexts – the intensional ones – are sensitive to differences of intension, while others – extensional ones – are not. For instance, belief ascriptions are intensional contexts. Extensionally speaking, it just as true to say (as the legend goes) that Oedipus has been having sex with his mother (from whom he was separated as an infant) as it is to say that he has been having sex with Jocasta. But as long as Oedipus is unaware that Jocasta is his mother, it is false to say that Oedipus believes that he has been having sex with his mother, although it is undoubtedly true that he believes that he has been having sex with Jocasta. ‘Jocasta’ and ‘Oedipus’s mother’ extensionally refer to the same woman in these contexts, but they have different intensions, and belief-reports (but not simple fact-reports) are sensitive to this difference.

Okay, that’s the set-up. Here’s how it all connects with natural selection: according to Fodor and Piattelli-Palmarini, the Darwinian theory of natural selection requires a notion of “selected for”. According to the theory, phenotypic traits (like the trait of having eyes) are biologically “selected for” because they enhance fitness. But, according to the authors, ‘selected for’ constitutes an intensional context: it has to distinguish between traits that are co-extensive, and it can’t. Let’s return to our arches and spandrels example to explain why. If nature, rather than human architects, had naturally selected arches for their structural enhancement properties (maybe because the environment happens to be such that cathedral-shaped organisms thrive), it would be just as correct to say that the spandrels had been “naturally selected for” as it would be to say that arches had been naturally selected for, even though spandrels are merely “free-riders” on the arches; they are not causally responsible for the arches’ fitness-enhancing properties. Hence, Darwin’s theory of natural selection supposedly has a serious conceptual problem.

I haven’t yet read the book, so I may have misrepresented or left out important details. However, Fodor lays out the basic idea to non-specialists at the University of Delaware in an audio recording available here and at iTunes U, and I’ve tried to reflect its content. Here is a brief excerpt, where Fodor lays out the central argument-

Is Fodor right about this? If so, should it matter to biologists? The standard interpretation of quantum physics apparently violates basic principles of deductive logic, but that doesn’t seem to disturb many physicists…

For most Americans, including me, the war in Afghanistan is a distant abstraction, something talked about but never even indirectly experienced. Restrepo, the recent documentary by Tim Hetherington and Sabastian Junger, helps to correct that deficit by showing the war from the perspective of American soldiers ordered to build an outpost in the heart of Taliban country. What it most clearly reveals, besides the mentality that the soldiers must adopt to survive, is just how out-of-kilter the mission of winning hearts and minds is from the cultural reality in rural Afghanistan. The scenes of the soldiers participating in weekly meetings with the local tribal elders demonstrate just how wide the gulf between the sides seems to be. They demonstrate this not so much by what is said, as by the elders’ facial expressions – expressions that are truly worth thousands of words. The strategy recently adopted by President Obama and General Patreus includes abandoning Restrepo (the outpost), and it seems to me that the documentary provides some grounds for thinking that this is necessary, despite the sacrifices of the soldiers who built it. But it also makes me wonder whether the entire project of trying to shape the future of Afghanistan suffers from a similar problem. Given the prospect – particularly for Afghanistan’s women – of the Taliban returning to power, I hope that it does not.